An earthquake impact (or damage) index is used to quantitatively approximate the impact or damage caused by an earthquake to a pre-defined portfolio of values of property or non-property nature, associated with different geographical locations, e.g. a portfolio relating to buildings, bridges, highways, power lines, communication lines, manufacturing plants or power plants, but also non-physical values, e.g. business interruption, contingent business interruption values or exposed population, based solely on physically measured and publicly available parameters of the earthquake phenomenon itself. An earthquake impact index is based on a pre-defined set of rules and can be assessed immediately after the earthquake. Defining the earthquake impact index solely on a measured magnitude of the earthquake has the disadvantage that there is no consideration of the portfolio and its geographical distribution of objects. Consequently, an earthquake impact index based solely on the magnitude of the earthquake correlates poorly with the true damage caused to the assets (objects) included in the portfolio. Particularly, with an increase of the geographical area in which the geographical locations are distributed, the magnitude based impact index shows an increasingly poor correlation with the true damage. Thus, other methods use other physical parameters of an earthquake occurrence than magnitude, i.e. earthquake shaking intensity in form of peak ground acceleration or peak ground velocity. Such parameters depict in areas of the world equipped with a dense net of seismograph stations a map of the aerial extent of earthquake shaking intensity, rather than only a single point measurement of the magnitude. Combining the aerial extent of earthquake shaking intensity with the distributed portfolio of objects allows for a much better correlation of the thus deducted earthquake impact index with really occurred impact or damage to the portfolio, while not sacrificing the immediateness of applicability after the event, as well as transparency to anyone willing to set up the computing procedure. However, owing to the cost of installation and maintenance, an infrastructure with a network of geographically densely distributed seismological measurement stations is currently not available in the majority of countries.